Little is known for certain of Shetland in early times. If by Thule, visited and described by Pytheas of Massilia, the ancients meant Shetland, then the first mention of the islands in our era is when Tacitus, telling of Agricola’s fleet in 84 A.D. says “Dispecta est et Thule,” assuming that it was really part of Mainland that the sailors descried in the dim distance. Irish missionaries christianised the natives in the sixth and seventh centuries. The nearness of the islands to Norway naturally led to visits from the Viking raiders and finally to conquest and settlement by them in the ninth century. The Norsemen found two races of people—the Peti or Picts, and the Papae, descendants of the Irish missionaries. Whether these were exterminated or absorbed by the invaders is disputed; but Christianity disappeared before Odin, Thor and other Scandinavian deities.

For several centuries after this, the history of Shetland is hardly separable from the history of Orkney, and that has been already narrated.[3] Though both groups of islands formed one earldom, Orkney was the predominant partner. Shetland received scant attention except as a recruiting ground for fleets or armies. From 1195 to 1379 Shetland was disjoined from Orkney; and, while the latter came more and more under Scottish influence, the former remained under Norse. It was during the period of separation that Norse influence impressed itself most strongly on Shetland.

Norse Shetland had its Althing or Parliament, meeting on the holm in Tingwall Loch under the presidency of the Foud. Each district had its lesser Thing (as Aithsting, Nesting) and its under-Foud, who selected Raadmen or Councillors, and was assisted by the Lawmen or Legal Assessors. The Lawrightman superintended the weights and measures—an important office, since rents and duties were paid in kind. The Ranselman was a kind of parish constable.